The present invention relates to a system for transmitting an ignition signal from a single detonator to a plurality of transmission lines connected to other detonators for the purpose of producing a predetermined, timed blasting pattern. In particular, the present invention relates to a system for controlling the ignition of a series of non-electrical detonators.
In non-electrical detonation of explosives, signals are transmitted between lengths of detonator cord, known as "shock tubes," by employing connector blocks. A connector block typically includes a detonator receiving the detonation signal from its own shock tube, a housing to contain the explosive effect of the detonator and limit the production of shrapnel, and a mechanism for securing a plurality of shock tubes adjacent the charge within the detonator. Upon ignition of the charge within the detonator, signals are generated within the shock tubes held with the securing mechanism. Examples of conventional detonator blocks include those described in U.S. Pat. No. 5,171,935, U.S. Pat. No. 5,204,492, U.S. Pat. No. 5,423,263, U.S. Pat. No. 5,458,611, and U.S. Pat. No. 5,499,581, U.S. Pat. No. 5,703,319, and U.S. Pat. No. 5,792,975, which are incorporated herein by reference.
Conventional shock tube connector systems are limited in a number of ways. For example, they generally can hold a maximum of four to six shock tubes, which limits the number of circuits that can be initiated from a given connector block. Moreover, most connector blocks create a variety of spatial relationships between the explosive charge within the detonator and the several shock tubes held by the block, which often results in inconsistent signal transmission to the individual shock tubes. In addition, to the extent more powerful detonator charges are employed to ensure adequate signal transmission to all shock tubes, not only does the cost of the system increase, but increased shrapnel may result.
It is the intention of this invention to provide a connector block that can hold up to eight shock tubes and effect signal transmission between the detonator and all eight shock tubes.
It also is the intention of this invention to provide a shock tube connector system that utilizes a modified detonator to transmit detonation signals efficiently and consistently to a plurality of shock tubes.
Additional advantages of the present invention will be set forth in part in the description that follows, and in part will be obvious from that description or can be learned by practice of the invention. The advantages of the invention can be realized and obtained by the apparatus particularly pointed out in the appended claims.